And we begin with the stunning confirmation from the prime minister Malaysia. The disappearance from the flight was not an accident. Because of a signal discovered on a satellite the search area different. In the first days after the plane went missing in the China sea. Tonight, they're now searching along the two red arcs you're about to see on the screen. Possible paths picked up on satellite. The prime minister calling it a deliberate action. David good evening. A deliberate act. A source says it's most likely the search will be concentrated on the southern route with the focus off western Australia O'. Because the jet could have flown for an hour. There's at least a 1,200 mile search area. A couple of Australian aircraft flew over the area. Their fuel range is limited. Naval resources will be necessary. Now it appears this was no accident. With equipment shut down and several turns. This movement is consistent with deliberate action by someone on the plane. Reporter: Here's why. Take off at 12:41. And tonight we learned whoever was at the controls programmed a left turn. Moments later a data system shut down. Then that program turned. Back over Malaysia. The 777 last seen at 2:17 P.M. But unbeknownst to the person at the controls the jet was signaling a satellite every hour. Not precise. Giving us those two corridors. The southern one uncovered by radar, all suggesting a hijacking. Or a rogue pilot. Someone taking command or already having command and I'm afraid the intent is lethal. If it is one of the pilots. What happened to the other? Inside the cockpit a crash ax. The pilot can depressurize the cabin. Those oxygen masks only last for a period of time Get rid of any opposition of whatever it is your trying to do. As a remember guide pilot. The first turn was preprogrammed was in evidence that someone was in control of this aircraft. Either a high jacker with flying knowledge or a rogue pilot. David. I want to bring in ABC's aviation analyst. You heard David router, a preprogrammed left turn. If that is the case, this is huge. En extraordinary piece of the puzzle. This would be the third premeditated action in the cockpit. Where they preprommed in the computer. Not easy for a Laman to do. It was probably somebody who had extensive training who preprogrammed this turn. We were talking about waters with 600 feet deep. Tonight we're looking at the Indian ocean. 15,000 deep. What does that make this process? Extremely difficult. You're talking about a depth of 12 empire state buildings deep. This is a much much tougher problem than it would have been than in the south China sea. It's like the TV show lost. Is it possible that this jet could have landed undetected some place? It's possible. It's highly unlikely. I think we're just hoping against hope.

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